The sounds of thought: Detectable or too abstract?

Technological advances in the last several years (such as Japan's "dream machine") have given us crude glimpses into the visual component of the thought process. Is it possible to do the same with the auditory component of thoughts? Is there any scientific evidence suggesting that thought sounds have a detectable frequency? This is not an attempt at philosophy--I want to know if there's a physical or quantum mechanical basis for these sounds, because I refuse to believe that it's some magical process that can't be explained.

There is a lot of work on decoding brain activity, but at the moment it isn't particularly sophisticated. Basically, you can present a person's brain with 1000s of stimuli, and measure the resulting brain activity in each case. Then you present a novel stimulus and try to see which of the previous stimuli the brain activity most closely resembles.

Thoughts aren't a real sound, they are the result of activity in neural circuits. On the other hand, every sound you have ever heard was the result of activity in these neural circuits, since that's the only way you can hear. At the moment this does seem a bit magical, since we don't know how brain activity gives rise to a subjective feeling of sounds etc., but people hope to one day understand it.

A neural circuit is a loose term used to describe a collection of interconnected neurons which process information by their patterns of activity in response to some kind of an external input. A lot of work in neuroscience at the moment focusses on how these circuits process information. If we can understand how they encode information, we would then be able to decode them as you say. This research topic is called neural (de)coding. Have a look at these links for more information: